Part 1 - General information
1) Select the Criteria for design (ex: City of Houston)
This is done by selecting the pulldown list box with your mouse.
2) Select your design storm (ex: 2-year)
3) Fill in project detail information.
4) Fill in area names for your drainage areas.
(notice as you fill in the area names the program autofills the inlet names.)
5) Fill in the respective drainage area sizes (in acres)
6) Fill in the runoff coefficient for each area.
7) Fill in the Manning "n" value for each area
8) Fill in the Length of each run of pipe
9) Fill in the Grade (ft/100ft) each pipe will be laid at.
10) Fill in the down stream flowline for the last pipe in each grouping.
11) Fill in the Inlet elevation for each inlet
12) Fill in the proposed ground elevation Upstream and Downstream for each pipe
13) Fill in the K factor for each junction.
Part 2 - Link it all together
Each lead coming into the Main Trunk or another lead must be linked in order to link the lead to the main trunk you need to add the Total Area Column for the lead to the Total area Column where the flow is entering the trunk. The downstream flowline of the lead needs to be linked in the same manner.

Calculation Reference
Storm water
Sewer design
Rainwater engineering

Calculation Preview

Submitted On:
07 Dec 2009
File Size:
104.00 Kb
File Version:

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Comments: 1
infostar 3 years ago
Thanks for creating the tool. While using the tool, I have noticed that the time of concentration formula seems to be not working. Perhaps, I am missing something. Please let me know, if you have detailed instructions to follow or an updated version of this tool that you can share. Thanks, Aravind